1. Field of the Invention
This invention relates to tilling the soil and more particularly to pulling tillage implements behind farm tractors.
2. Description of the Prior Art
The present day farm tractors commercially in use commonly have two rear traction wheels and two front steerable wheels. When pulling heavy loads it is desirable to have as much weight as possible upon the traction wheels. Also, the standard farm tractor has a three-point power and draft linkage having two lift links and a stabilizing link. The lift links are connected to the power system of the tractor so they may be raised and lowered, thereby raising and lowering any equipment attached thereto. On modern tractors, the raising and lowering is by the hydraulic pressure system of the tractor and a valve is provided within easy reach of the operator so he can readily raise and lower the three-point power linkage.
Previous workers in the field suggested that when tractors are towing trailers, booms should be attached to three-point linkage and a tension member extended to the tongue of the trailer. The purpose of this was to transfer weight to the rear traction wheels.
SUTHERLAND, U.S. Pat. No. 2,673,092, showed such a mechanism with springs extending from the boom to the trailer tongue.
HODGES ET AL, U.S. Pat. No. 3,347,560, shows a swinging boom which is mounted on an angled axis so that as the tractor turns, the boom lowers, thereby reducing the transfer of weight on tires.